With the development of modern equipment manufacturing towards large-scale and precision, large-diameter blind hole roller forgings, as key basic components, are increasingly widely used in fields such as energy, aviation, and heavy machinery. Among them, blind hole structure, as a common functional feature, its processing quality directly affects the performance of the product in use. However, the traditional blind hole processing methods for large-diameter forgings are confronted with problems such as high cost and low efficiency, which seriously restrict the market competitiveness of enterprises. This paper addresses the challenge of cost control in the processing of large-diameter blind hole roller forgings and systematically analyzes the technical principle and implementation path of the integrated forging process. By optimizing the forging process design and integrating blind hole forming into the manufacturing process of forging blanks, the subsequent mechanical processing volume is significantly reduced, thereby achieving the goal of cost reduction and efficiency improvement. The research results have significant practical significance for improving the manufacturing level of large forgings in our country and enhancing the cost competitive advantage of enterprises.
I. Analysis of the Reasons for the High Processing Cost of Large-diameter Blind Hole Roller Forgings The high processing cost of large-diameter blind hole roller forgings mainly stems from three aspects: severe material waste, long processing cycle and high equipment energy consumption. The traditional processing methods usually adopt solid forging blanks, and form blind hole structures by removing a large amount of material through cutting, resulting in a material utilization rate generally below 50%. This "subtractive manufacturing" model not only wastes expensive alloy materials but also incurs a large amount of waste chip processing costs. In terms of processing cycles, blind hole structures typically require multiple procedures to be completed, including rough machining, semi-finishing, and finishing, etc. Each procedure demands dedicated machine tools and clamping positioning, resulting in a lengthy production process. Take a forging with a diameter of 800mm as an example. Traditional blind hole processing often takes 40 to 60 hours, becoming the bottleneck link in the entire production process. The issue of equipment energy consumption is equally prominent. The processing of large-diameter blind hole roller forgings requires high-power machine tools to operate for long periods of time, consuming a huge amount of electrical energy. At the same time, to meet the requirements of processing accuracy, high-value cutting tools are often needed and replaced frequently, which further increases the production cost. These factors collectively result in the blind hole processin cost of large-diameter forgings accounting for as high as 30% to 45% of the total manufacturing cost, making it a key and difficult point for enterprises to control costs. The core idea of the integrated forging process is to complete the formation of blind hole structures in the forging stage in advance. By optimizing the mold design and forging parameters, large forgings with blind hole characteristics can be directly obtained. This "near-net forming" technology significantly reduces the amount of subsequent mechanical processing, achieving a transformation from "subtractive manufacturing" to "additive manufacturing".
The key to the implementation of the process lies in precisely controlling the flow and deformation of the metal. By adopting multi-directional die forging technology, the inner cavity structure of blind holes is simultaneously formed during the forging process. This requires a comprehensive consideration of factors such as material deformation resistance, flow characteristics, and temperature field distribution to design a reasonable forging process and die structure. Meanwhile, to ensure the dimensional accuracy and surface quality of blind holes, it is also necessary to optimize the lubrication conditions and cooling methods. Compared with traditional craftsmanship, integrated forging has obvious technical advantages. Firstly, the material utilization rate can be increased to 75%-90%, significantly reducing the cost of raw materials. Secondly, reduce the mechanical processing volume by 60% to 80% and shorten the production cycle. Secondly, the energy consumption of equipment and the consumption of cutting tools have been reduced, resulting in a significant decrease in the overall processing cost. In addition, as the metal flow lines remain intact, the product quality and mechanical properties have also been improved. Iii. Key Points for the Implementation of Integrated Forging Process To successfully implement the integrated forging process, several key technical points need to be grasped. Mold design is fundamental. It is necessary to precisely calculate the metal volume and flow path required for blind hole forming, and design a reasonable parting surface and draft Angle. For complex blind hole structures, combined molds or floating core technologies can be adopted to ensure the forming quality and mold life. The optimization of forging parameters is of vital importance. The optimal starting forging temperature, final forging temperature and deformation rate should be determined based on the material properties to avoid defects such as folding and incomplete filling. For high-alloy materials, it is also necessary to control the deformation amount of each pass and the holding time in the middle. Practical experience shows that the application of isothermal forging or quasi-isothermal forging techniques can effectively improve the quality of blind hole forming. The quality control stage should not be overlooked either. A complete inspection system should be established to strictly inspect the blind hole size, wall thickness difference and surface quality of the forging blank. Introduce non-destructive testing methods such as ultrasonic flaw detection to ensure that the internal structure is dense and defect-free. In addition, it is necessary to enhance the collection and analysis of process data
Fourth, Conclusion: The integrated forging process provides an innovative and low-cost solution for blind hole processing of large-diameter forgings. By integrating blind hole forming into the forging process, this technology has achieved a simultaneous improvement in material utilization rate, production efficiency and product quality. Practical experience has shown that the rational application of this technology can reduce the cost of blind hole processing by 20% to 35%, bringing about significant economic benefits.